Concrete step form



April 15, 1952 KOGL 2,592,578

CONCRETE STEP FORM Filed April 28, 1947 7 Sheets-Sheet 1 FIE l gwvexwtoaFRANK KOGL 5- April 15, 1952 F. KOGL CONCRETE STEP FORM 7 Sheets-Sheet 2Filed April 28, 1947 FRANK KOGL mwww April 15, 1952 F. KOGL CONCRETESTEP FORM 7 Sheets-Sheet 3 Filed April 28, 1947 z 5 7 0 W v m 2H,. 4 9 I4 a; H A a I u a 4 u o n n m 4 5 6 w o u n i m. L2 T4 2 m n A 4.. L (m a8 ml: 9 w a GI 6 FRANK KOGL A ril 15, 1952 F. KOGL CONCRETE STEP FORM 7Sheets-Sheet 4 Filed April 28, 1947 ZM/ 3 K M/ ma Q m April 15, 1952 F.KOGL 2,592,578

' CONCRETE STEP FORM Filed April 28, 1947 7 Sheets-Sheet 5 PIE 5 FRANKKOGL April 15, 1952 F. KOGL CONCRETE STEP FORM 7 Sheets-Sheet 6 FiledApril 28, 1947 FRANK KOGL April 15, 1952 F. KOGL 2,592,578

CONCRETE STEP FORM Filed April 28, 1947 7 Sheets-Sheet '7 FIE 1E 63gwue/wbo n FRANK KOGL MZLM+ A Q Patented Apr. 15, 1952 CONCRETE STEPFORM.

Frank Kogl, St. Paul, Minn., assignor of two and one-half per cent toWalter H. Carlson, tw'oand one-half per cent to Ora E; Carlson, West St.Paul, four per cent to Minnie M. Clark, four per cent to GenevieveClark, South St. Paul, Minn.-, andten per cent'to Richard L. and RubyS.- McBridev Flynn, Superior, Wis.

Application April 28, 1947, Serial No. 744,430

7.Claims. (Cl. 25.1'18.) 1

This invention relates to. improvements in forms forprecastingmonolithic concrete 1 step structures.

The primary. object isto provide an improved form for this purpose whichwill permit con crete stairs or steps to be rapidly poured and cast as aunit and which formmay be readily used to cast different numbers ofsteps'or even several castings at a time. A further object is to providea form which may be easily set upfor receiving the concrete and thenvtaken down to remove the cast steps. Still a further object is toprovideheating meansfor quickly and effectively curing the concrete tospeed up the operation of the form. Another object is to provide a formwhich is designed to. cast a predetermined number of steps but which maybe partially removed when a number of step structures having fewer stepsare to be cast, or which.alternatively may be used without suchdisassembly to castfewer steps when only a few such.

structures are required. Another object is to provide a form which willmake an improved product, easily handled, with provisions for.

lighting andheating and otherxadvantages as will presently appear.

These and other more: detailed and specificobjects will be disclosed inthe course of the following specification, reference being had to theaccompanying drawings, in which- Fig. 1 is a side view of the form incasting position, mounted upon a supporting frame or fixture andillustrating one manner in which the number of steps cast in the' f'ormmaybe reduced.

Fig. 2 is an elevational. and sectional view taken substantially alongthe line 2-2 in Fig.1.

Fig. 3 is a vertical sectional view of the form in Fig. 1.

Fig. 4 is .a side elevation of the form supported ona skid in positionfor stripping it from a cast structure and showing this operation .inprocess.

Fig- 5 isa fragmentary sectional View of. the

. upper part: of l the form, inthis caseused for theiupper'part of. theform showing a different manner of cutting or stopping off the formtoreduce the number ofsteps. cast therein.

Fig. 9 is an enlarged fragmentary detail sectional view of apart of theform ass'een in Fig. 8.

Fig. 10 is a sectional view along the line l0l0 in Fig.9..

Fig. his a detail in elevation of one'of the removable cover or sideplates, notched foruse in the form of Figs. 8 to 10.

Fig.12 is a vertical section illustrating still another use of the form.

This application discloses a form which is an improvement over :my priorPatents No. 2,161,822 issuedJunel'Bth, 1939; No. 2,281,698 issued May5th, 1942; No. 2,331,701, issued October 12th. 1943, and No. 2,353,676issued July 18th, 1944, and is in several respects quite similar to theform of the latter patent. The present form further is used inaccordance with the casting methods taught. in my Patent. No. 2,289,439.issued July 14th, 1942. I

Referring now more particularly and by refer,- ence characters to thedrawing, the form'constituting my present invention comprises basicallyan outer form indicated generally at A and an inner form indicatedgenerally at B which is positioned within and spaced from the outer formto provide a casting cavity shaped and adapted to form a plurality ofsteps and sides therefor. In the present case the form'is made to cast aseriesof four steps having treads C and risers D and with a rearwardextension of the, uppermost step forming a platform'E. In the. finishedcast structure there will also be formed sides as indicated at F whichextend downwardly from the platformv and steps so that the casting hasan open bottom and back but theis otherwise completely hollowtherewithin closed. The cast structure is thus substantially identicalto that formed by the mold in my Patent No. 2,353,676.

The: outer form A comprises one piece side These members, I5 to [8, areall identical in construction and each comprises a riser forming plateI9 and a tread forming plate which, where they join, are forwardlybulged as indicated at 2| to form a nosing along the forward edges ofthe steps. It will be noted that the contiguous portions of the sidepanels ID are similarly formed as indicated at 22 so that this nosingextends also the full width of the treads C. The lowermost step formingmember |5 has an angle iron 23 extending along its lower edge andcorresponding in function to the angle irons l2 upon the side panels.This member I5 then extends not quite to the junction of the lowermosttread C with the next riser and this edge is also provided with an angleiron 24 adapted to fit against a similar angle iron 25 upon theforwardly turned edge portion 26 of the next step forming member IS. Theupstanding webs of the angle irons 24 and 25 are secured together in anysuitable manner such as by means of the bolts 21 and in a similar mannerthe step forming members l6, l1 and [8 are all joined together alongcorresponding edges and by corresponding parts as seen in Figs. 1 and 4.Thus, while all of the step forming members |5 to l8 are normallysecured together as a unit, they may be each separated from the otherwhenever desired. The uppermost member I8 also has an angle iron 28along its rear edge which fits against a similar iron 29 secured to aplatform plate indicated at 30. These parts are connected by bolts 3| sothat the plate 30 forms a rearward continuation of the upper step formto define the outer or upper surface of the aforesaid platform E.Preferably, the platform plate 30 is also divided into sections asclearly shown in Fig. 4 joined by angle irons 32 and bolts 33 so that ahalf or short platform may be cast when desired.

To hold the assembled step forming members I! to |8 in place on theouter form, I provide them at the ends of their vertical riser formingplates IS with fastening bars 34 which fit against the outwardly turnedwebs of short angle iron bars 36 welded to the adjacent vertical andforward edges of the side panels Ill. These bars are apertured toreceive bolts 36 as seen in Fig. 1 which will anchor these parts of theform together. The horizontal tread plates 20 are also provided with endbars 31, which project far enough to clear the nosing forming bulges 22,

and which are notched as indicated at 38 for en" gagement by wing nuts39 upon clamp bolts 40. These clamp bolts 40 are pivoted at 4| upon theside panels l0 and in normal position they extend upward so that whenthe wing nuts 39 are tightened the step forms will be pulled tightly toplace. The end bars 38 are also apertured as indicated at 42 to fit dwnwardly over pilot or locating pins 43 welded to the side plates to further anchor the step forms in place. The platform plate 30 is alsoanchored in place by the same means including the end bars 38 and thehinged clamp bolts 40 having wing nuts 38.

The inner form B also has side panels 44 with stiffening bars 45 and 43around its lower and rear edges, but in this case the transverseportions of the form comprising the tread forming plates 41, riserforming plates 48 and platform plates 49, are all welded or otherwiserigidly secured to the side panels. Thus, the inner form is effectivelya one piece affair and it is, of course, so shaped and sized that, wheninserted into the outer form with lower and rear edges aligned, therewill be formed a casting space which not only is shaped to mold thedesired component parts of the monolithic stair structure, but is of thedesired width at all points to provide adequate strength. It willfurther be understood, as has been pointed out in my previous patents,that this inner form will have a slight taper or draw so that it may bereadily withdrawn from the cast structure after the casting operation iscompleted.

In the casting position the assembled form is supported in an erectposition upon its forward end as seen in Figs. 1, 2 and 3 so that theopen rear end of the casting cavity between the inner and outer forms isturned uppermost. To support the form in such position, I provide aframe or fixture indicated generally at G having a base 50 from oppositeends of which are erected irregularly shaped end frames 5! across whichare secured a plurality of horizontal supports 52 and vertical supports58. These supports 52 and 53 may be lumber of a common dimension and areadapted, respectively, to engage the now downwardly turned riser formingplates Hi and the vertically turned tread forming plates 20. Thesupports 52-53, may, of course, be recessed whenever necessary to clearbolts and other projecting parts. The supports 52, of course, thussupport the weight of the form, and to hold the form in place I providedraw bolts 54 which are adapted at one end to be fitted to brackets 55upon the side panels l0 and at their other ends are placed throughbrackets 56 extending from the vertical supports 53. When these drawbolts 54 are drawn up tight, they will obviously securely anchor theform to the fixture G. The two uppermost vertical supports 53 engage andsupport the sectional platform plate 30 as clearly shown.

In casting position the normally lower edge of the form is positionedvertically and this edge is closed by a U-shaped cover plate indicatedgenerally at 51, the width of which is sufficient to overlap the innerand outer angle irons l2 and the corresponding angle irons 23 and 58upon the inner and outer forms. The plate 51 has a plurality of openingsto pass pilot or locating pins 59 extending from the angle irons and theplate is held to the angle irons at a plurality of points by means ofclips indicated generally'at G6 which may be drawn tight and hooked overthe edges of the plate and irons. These clips and their uses aredescribed in greater detail in my Patent No. 2,353,676 and will not befurther described herein. Ordinarily, the plate 57 will extend to thetop of the form in its casting position but the plate is made insections along its vertical portions as seen in Fig. 2 so that it may beapplied to the form to any desired level for purposes presently toappear.

To hold the forms in their assembled position and support the inner formin properly spaced relation to the outer, I provide hanger bars 6| whichextend across the top of the form in its casting position and which arebolted to the angle irons l3 on the outer form and to correspondingangle irons 62 upon the inner form. When so mounted, these hanger bars6| will obviously largely support the weight of the inner form but Ialso provide the bars with cranked, threaded studs 63 which are threadeddownwardly through the ends of the bars in position to engage theoutermost form. Thus, as has been pointed out in my prior patent justreferred to, it is possible by removing the bolts connecting the crossbars to the outer form to elevate the inner form merely by turning thestuds 63 downwardly so that they bear downwardly on .the outer form.This is oi. advantagein breaking the inner'form loose from the caststructure when the form is stripped from. thecasting as will laterappear,

In the" use of the form as thus far described, it

willbeapparent that the. casting cavity, may be.

The .vibration imparted to the-mold by operation.

of the vibratoris very effective in causing the material to properlysettle and distribute itself and in theuformation of a. dense,- smoothsurface in casting. When the mold has been filled, it must,.of course,be left in position untilthe casting cures. to a point permitting themold. to be removed without breakage and to speed up this curingoperation, which obviously controls the time between casting operations,I provide in the'fixture G heating means in the form either of a steamcoil or helix, 68 or electric lamps 69, or both. Thus, as soon as thecasting has been completed, a canvas or the like may be thrown over theentire form and the heat provided by the element 68 or 69 willmaterially advance and. speed up the curing cycle. Another steam coil 68may be placed in theform as seen in Fig. 2 upon a fitting 68 When ready,the entire form is lifted from the fixture G and for this purpose Iprovide, asin my earlier patents, a bail indicated generally at 10,whichis pivotally attached at H to opposite sides of the outer form. Thepins 1| forming this pivot connection are adjus -ably mounted inangularly extending guideways 12 secured to the side panels Ill. and byproper adjustment thepivot axis may! be so located with the respectxtothe center of gravity of the form that it will be nicely balanced.- inthe bail 10. The entire inner form B may be pulled as aunit from theinside of the casting after the clips 60 are removed in an upwarddirection while the form is still supported in the fixture G and to thenhold the casting in.

place in the outer form cross bars (not shown here) may be temporarilyfastened between the side panels I after which the outer form with itsenclosed casting may be rested upon a skid or. structure indicated at 13as seen in Fig. 4. By then removing the bolts 36 and loosening the wingnuts 39, the transverse platform and step forming portions of the outerform may be lifted up and swung clear as seen in Fig. 4 and when theside panels ID are pulled away, the casting will be left supported uponthe skid and may be moved away thereon for further curing and maturing.These form assembly and disassembly operations and methods have all beenpointed out in great detail in my earlier patents and should require nofurther description herein.

As thus far described, the form casts four steps, a platform and sides,all in an integral unit and is thus used to full capacity. Frequently,however, it is desirable to cast a structure having fewer than foursteps, and often as few as. just one, and in some cases the platform isnot desired or a shortened platform is desirable. Inl my previouspatents I have disclosed forms which may be partially taken down andadapted by such operation to casting less than the full number of stepsor for eliminating the platform. extension, but in the. present instanceI provide-means which will permit my form to be used for this purposewithout disassembly. As shownin. Figs. 1 to 4, I accordingly provide theside panels) of.

the outer form with openings 74 adjacent the junction of the treadsandrisers of the four steps,-

and these openings are thus threein'number for each side panel. Theopenings '14 are located iminediately adjacent the points at whichtheitreadsi 0 meet the risers Dand thelower edgesof the openings areexactly horizontally ali ned with these points as seen in Fig. 1. Aroundthe openings I then provide stiffening frame bars andthese frames arespaced outwardly from the ad jacent edges of the openings as shown both:in-

Fig. l and Fig. 7. Normally fitted in the openings 14 are closure orcover plates TBwhich alsohave stiffening frames 1! extending beyond theedges of the plates and adapted to nicely fit with in the frame 75 aswell as to overlie the exposed edges of the side panels I 0 and so bringthe plates. exactly flush on the inside with the inner surfaces of thepanels. The plates are held'in place by tapered keys 78 which are passedthrouglj loops 19 on the opposite sides of the frame-"l5 and which whendriven home bear inwardly upon the frame 1'! to securely lock theplates. Thus. so long as the openings 14 are covered, they willinterfere in no way with the normal operation; of the form in casting toits full capacity as will be understood.

Now, for example. if it should be desired to cast a few structureshaving only three steps without the platforms, the uppermost plates 16may be removed, as shown in Figs; 1 and 2, and thus the casting cavitybetween the forms will be exposed at this level so that the cementitiousmaterial may be poured only into the lower part of the form up to aboutthe level of the lower edges of the openings. When the material reachesthis level it may be surfaced off at what will then be the rear edge ofthe uppermost tread by the introduction through the openings 14 of astriking or scraping bar 80 which will then extend transversely throughthe form and may be worked back and forth to smooth off the material.When the form is so used, the upper few sections of the upright parts ofthe plate 51 will also be removed as in Figs. 1 and 2 and it will benoted that these sections are of such length that when removed in properunits the remaining upper edges of the plate will line up nicely withthe lower edge of the opening (4. To then strike off the rear edge ofthe shortened sides F of the casting the striking bar 80 or a shortenedvar-- sion thereof may be guided in between the sides of the inner andouter forms and when rested upon the upper edges of the plate 51and'upon the uppermost riser forming plate I!) the bar will be so guidedthatthis edge will be struck off at the proper right angle with respectto the bottom of the casting. Thus, it will be seen that for any numberof steps from one to three, the form may be readily put to use merely byremoving the appropriate cover plat-es I6 and filling the form to thatpoint after which the material is struck off to provide the necessarysmooth edge.

Where a considerable number of one, two, or three step castings are tobe made, itmay be preferable, as seen in Fig. 5, to remove the upperpart of the outer form and the platformplate 3d and any one of the stepforming members the angle iron 24 of the uppermost remaining stepforming member to thus form the tread surface straight and even back tothe point at which it is cut off. Without the provision of some suchmeans it is obvious that the uppermost tread would be difficult to formto full width and the oar 82 overcomes this while providing a guide bywhich the rear edge of the tread may be readily troweled or smoothedoff.

It is possible also to form a false bottom for the forms in order toreduce the number of steps cast and thus permit the casting of one ormore steps with the integral platform E. This arrangement is shown inFigs. 8 to 10 and is used in connection with a form constructionidentically as just described. In this case, however, at the point atwhich it is desired to out off the form the adjacent openings 14 areexposed by removing the cover plates T6 thereat and a cross bar 84 isinserted endwise through these openings so that it crosses the bottom ofthe form exactly at the bottom of the lowermost riser D. This cross bar8 is trussed as indicated at 85 to prevent it from bending under theweight of the material and it is held in place by replacing the coverplate 56 with plates 86 having notches 81 to exactly fit and engage thebar. The bar 84 will, of course, be wider than the overall width of theassembled form in order to project outwardly through the notches 8? andwhen the plates 86 are installed and the key 18 is driven home, the barwill be held firmly in the lower corners of the openings 14. See Fig.10. To form and define the lower edges of the step sides I" in alignmentwith the lower edge of the lowermost riser D, I then provide verticalbars 90 which extend downwardly through the spaces between the inner andouter form sides and are trussed as indicated at 9!. The lower ends ofthe bars 96 are provided with depended pins 88 welded at 89 and thecross bar 84 has loops 88 to receive the lower ends of these pins tothus anchor the lower ends of the bars against displacement in anyexcept an upward direction. The upper ends of the bars 90 are joined toangle irons 93 which may then be bolted across the top of the form asindicated at 94. Bars 84 and 90. when thus installed, form a U-shapedcut off or false bottom for the form allowing it to be filled to anydesired level and as seen in Fig. 8, it is installed for casting a twostep structure with platform. Obviously, where three steps are cast, thebars 8!) will be replaced by others of the proper length to fit.

In each outer riser forming plate ii], I provide one or more openingsthrough which may be introduced cap screws 95 for anchoring taperedplugs 96 in the space between the forms. When these plugs 35 are usedthere will obviously be formed in. the risers D an equal number ofinwardly tapering openings 9'! as best seen in Fig. 6. These openings 91provide convenient means for the installation of electric bulbs 98 forlighting the treads at night and as here shown, the bulbs 98 areinstalled in sockets 99 secured within the step structure and the bulbsare protected by transparent lenses N10. The installation also lendsitself to the use of conventional resistance wire heating units IUI inthe inside of the step structure by the use of which the steps may bewarmed in winter to prevent the accumulation of ice or rid the stepsthereof. When this is not desired in the castings, the plugs may, ofcourse, be omitted and the openings for the cap screws plugged up in anysuitable manner.

Also, as seen in Fig. 3 I may employ a plug 96 at each upper side of theform in order to provide transversely aligned openings I02 in the sidesF immediately beneath the uppermost step. These openings may bedesirable to facilitate the handling of the castings since a pipe orother tool may be readily thrust therethrough to facilitate carrying, aswill be readily apparent. These openings Hi2 also provide a verydesirable ventilation for the hollow inside of the steps.

It is possible with my present form to cast a plurality of separatestructures each operation. Referring to Fig. 12 I show therein a lowereasting having two steps indicated generally at I and J with integralsides K. and an upper casting having two steps L and M, with platformextension N and integral sides 0. The form itself is identical to thatpreviously described and for this use the form is first filled to thelevel of the middle openings 14 from which the cover plates 16 areremoved and the upper edges then finished off by the striking bars Bilas in Fig. 3. The bars 84 and 90 are then installed at these openings,as described and as shown in Fig. 8, after which the form is filled tothe top as will be readily apparent. Thus, the form is at all timesworked to full capacity.

It is understood that suitable modifications may be made in thestructure as disclosed, provided such modifications come within thespirit and scope of the appended claims. Having now therefore fullyillustrated and described my invention, what I claim to be new anddesire to protect by Letters Patent is:

1. In a form for casting a series of concrete steps and sides thereforin a monolithic unit, inner and outer spaced forms having portions forshaping the treads and risers of the steps and the sides therefor, thesaid form while casting being supported on end with its rear enduppermost for pouring the material downward into the space between theforms toward the front end or lowermost step, the sides of the outerform having openings through which material may be poured and a toolintroduced to surface oil the material, and cover plates removablymounted over the openings.

' 2. In a form for casting a series of concrete steps and sides thereforin a monolithic unit, inner and outer spaced forms having portions forshaping the treads and risers of the steps and the sides therefor, thesaid form while casting being supported on end with its rear enduppermost for pouring the material downward into the space between theforms toward the front end or lowermost step, the sides of the outerform having openings through which material may be poured and a toolintroduced to surface off the material, cover plates removably mountedover the openings, and the said openings being located adjacent thejunction of the tread and riser forming portions of the outer form.

3. In a, form for casting a series of concrete steps and sides thereforin a monolithic unit, inner and outer spaced forms having portions forshaping the treads and risers of the steps and the sides therefor, thesaid form while casting being supported on end with its rear enduppermost for pouring the material downward into the space between theforms toward the front end or lowermost step, the sides of the outerform having openings through which material may be poured and a toolintroduced to surface ofi the material, cover plates removably mountedover the openings, and the said openings being located adjacent thejunctions of the tread and riser forming portions of the outer form andthe lower edges of the openings being horizontally aligned with thejunctions of the treads and risers.

4. In a form for casting a series of concrete steps and sides thereforin a monolithic unit, inner and outer spaced forms having portions forshaping the treads and risers of the steps and the sides therefor, thesaid form while casting being supported on end with its rear enduppermost for pouring the material downward into the space between theforms toward the front end or lowermost step, cut-off means positionedin the space between the forms for forming a false bottom at the levelof any selected step to reduce the capacity of the form, the saidcut-off means comprising a U-shaped assembly hung at its upper ends fromthe top of the form when it is in casting position and secured at itslower corners to the sides of the outer form.

5. For casting concrete steps with sides in monolith, a form structureof the character described having inner and outer forms respectivelyhaving tread and riser forming portions and sides for forming the sidesof the cast structure, means for supporting the forms in spaced relationwith an intervening casting cavity, and a U-shaped member positioned inthe form at the level of a selected step to reduce the capacity of thecasting cavity and cast fewer steps than the full capacity of the form.

6. For casting concrete steps with sides in monolith, a form structureof the character described having inner and outer forms respectivelyhaving tread and riser forming portions and sides for forming the sidesof the cast structure, means for supporting the forms in spaced relationwith an intervening casting cavity, and a U-shaped member positioned inthe form at the level of a selected step to reduce the capacity of thecasting cavity and cast fewer steps than the full capacity of the form,said U-shaped member having a cross bar to close the space between thetread and riser forming portions of the forms and connected bars forclosing the spaces between the sides of the forms. I

7. For casting concrete steps with sides in monolith, a form structureof the character described having inner and outer forms respectivelyhaving tread and riser forming portions and sides for forming the sidesof the cast structure, means for supporting the forms in spaced relationwith an intervening casting cavity, a U-shaped member positioned in theform at the level of a selected step to reduce the capacity of thecasting cavity and cast fewer steps than the full capacity of the form,said U-shaped member having a cross bar to close the space between thetread and riser forming portions of the forms and connected bars forclosing the spaces between the sides of the forms, and means separablyconnecting the respective bars making up said U -shaped member.

FRANK KOGL.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

